An­chor­age was pre­pared for two re­cent earth­quakes thanks to past ex­pe­ri­ence.

In decades since record quake, city bol­stered build­ing codes

AN­CHOR­AGE, Alaska — The mag­ni­tude 7.0 earth­quake that rat­tled Alaska’s largest city cracked roads and col­lapsed high­way ramps, but there were no re­ports of wide­spread cat­a­strophic dam­age or col­lapsed build­ings.

There’s a good rea­son for that. A dev­as­tat­ing 1964 Alaska earth­quake, the most pow­er­ful on record in the United States, led to stricter build­ing codes that helped struc­tures with­stand the shift­ing earth Fri­day.

“Con­grat­u­la­tions to the peo­ple of Alaska for be­ing re­ally pre­pared for this earth­quake,” U.S. Ge­o­log­i­cal Sur­vey Geo­physi­cist Paul Caruso said Satur­day. “Be­cause a mag­ni­tude 7.0 in a city like that, you know, it could have been sig­nif­i­cantly worse.”

Gov. Bill Walker said some­times peo­ple, in­clud­ing him, grouse about strin­gent build­ing codes. But he’s “re­ally glad” they were in place, as he had only mi­nor wa­ter dam­age at his home.

The quake was cen­tered about 7 miles north of An­chor­age, which has a pop­u­la­tion of about 300,000. Peo­ple ran from their of­fices or took cover un­der desks. A 5.7 af­ter­shock ar­rived within min­utes, fol­lowed by a se­ries of smaller quakes.

By mid-morn­ing, there had been about 550 af­ter­shocks, in­clud­ing 11 with mag­ni­tudes of 4.5 or greater, Caruso said.

The af­ter­shocks should be weaker and less fre­quent in the com­ing days, but of­fi­cials can’t say for sure when they’ll stop, he said.

An­chor­age Mayor Ethan Berkowitz said the ex­tent of dam­age was “rel­a­tively small” con­sid­er­ing the scale of Fri­day’s earth­quake. He also cred­ited build­ing codes for min­i­miz­ing struc­ture dam­age.

Af­ter the first earth­quake, Alaska’s largest hos­pi­tal ac­ti­vated its in­ci­dent com­mand cen­ter, but the trickle of pa­tients into the emer­gency room at Prov­i­dence Alaska Med­i­cal Cen­ter in An­chor­age was more like that of a nor­mal work­day and not a mass-ca­su­alty event. The in­juries were de­scribed as mi­nor, and there were no pa­tients with life-threat­en­ing con­di­tions.

Roads didn’t fare so well, as re­ports of ex­ten­sive dam­age came in. The Alaska Depart­ment of Trans­porta­tion counted about 50 sites with dam­age, in­clud­ing eight con­sid­ered ma­jor. Most of the dam­age was to high­ways north of An­chor­age. The agency also was plan­ning to in­spect bridges Satur­day.

The 800-mile trans Alaska oil pipe­line was shut down for hours while crews were sent to in­spect it for dam­age.

The state av­er­ages 40,000 earth­quakes a year, with more large quakes than the 49 other states com­bined. South­ern Alaska has a high risk of earth­quakes be­cause the Earth’s plates slide past each other un­der the re­gion, but it is rare for ma­jor quakes to strike so close heav­ily pop­u­lated ar­eas.

Dan Jol­ing The As­so­ci­ated Press

Re­pair work is done Fri­day to an of­framp that col­lapsed in the earth­quakes that hit An­chor­age, Alaska.